A “Search engine” is a system that searches for information that sustains some Search criteria. Regarding the Internet, a Search engine is a Web application that searches Web sites that sustain some Search criteria.
A search engine on the Internet usually comprises three parts:                A Spider-program (also called a “crawler” or a “bot”), which is a program that “visits” Web sites and reads their pages and other information in order to create entries for a search-index;        An Index-program, a program that compiles a massive search-index from the pages read; and        A Seeker-program, a program that receives search requests, compares each request to the entries in the search-index, and returns the results to the user.        
A search-index is a database that contains information about a set of Web sites. Using the search-index, a sub-group of Web-site(s) can be obtained according to search-criteria.
There are various search Web-sites that maintain databases about the contents of other Web sites. Yahoo was the first search Web site to gain worldwide attention, and it differs from most other search sites in that its content is indexed by people who create a hierarchical directory by subjects. As a result, Yahoo and similar search Web sites are technically called “directories” rather than “search engines”. Most directories offer a search engine mechanism to query the database.
Most other search Web applications are highly automated, sending “Spider” programs out on the Web around the clock to collect the text of Web pages. Spiders follow all the links on a page and put all the text into a database. Sometimes a Web site offers both—a search engine and directory capabilities.
Major search engines such as AltaVista and Google index the content of the Web, while directories such as Yahoo and Looksmart try to categorize it manually. However, due to the huge size of the Web and other objective reasons (such as connectivity of sites), Google indexed only 30% of the Web, while Yahoo indexed only 2% (according to the assessments of the Web size)
There are dozens of search engines, each with its own anchor Web site. Some search Web applications, such as Yahoo, search not only using their search engine but also provide the results from simultaneous searches of other search indices.
Usually, the above-mentioned search engines do not provide focused answers, since the same keywords may be found in Web sites of different categories and subjects, while the user is not provided with means for distinguishing between the results. Search results can span for pages, and consequently overwhelm the user.
Yahoo displays not only Web sites that contain the specified keywords, but also a list of categories that contain the searched keyword(s), as may be seen in FIG. 1. In the illustrated case, the word “chess” was searched. Hence, after obtaining the initial results, the user can focus his search by selecting the category best suited to the subject matter he is looking for. In that case, the search results are limited to the selected category as pre-grouped by the people of Yahoo. Such a search may be called a “context search”. However, the user is not provided with means for distinguishing the Web sites by importance or any other property. Moreover, since Yahoo does not scan the Internet by automated methods, each category contains a minor amount of Web sites.
Due to the fact that the categories of Yahoo were defined by a human factor and not by a machine, there are some ambiguities. For example, in FIG. 1, the hierarchy of the categories “Computers and Internet>Hardware>Systems>Macintosh>Software>Games” is odd since regarding to computers, the category “Software” is not a sub-category of “hardware”.
One of the options of the Google search engine, introduces a different approach. The search starts from a selection of one or more predefined categories and the search refinement is carried out by the topical keywords. For example, a user wishes to search for a free computer chess game. The user starts the search from a Web page (within the Google Web site) called “Web directory”, where he selects the category “Games”. Google displays a list of sub-categories, and the user selects the “Computer games” sub-category. The next category is “Windows”, and in this category Google displays the following answers: 3D Graphics (18 Web sites), Cheats and Hints (46 Web sites), Downloads (21 Web sites), Fan Fiction (11 Web sites), and Shareware (146 Web sites). When selecting the final directory, the user submits the keyword “chess” to limit the results to only chess games.
In matter of fact, Google uses the directory of Open Directory Project (ODP), rather then its own directory. ODP is an organization of more than 30,000 volunteers that index the Internet.
Google results are ranked quite differently from those of other search engines. Ranking in Google is carried out according to the site's importance as determined by the number of links pointing to a Web site. After obtaining a list of Web sites that meet a text-oriented search criterion, Google ranks the obtained list according to the number of links pointing to each Web site, and the results are presented according to this order.
The main drawbacks in the existing search engines are the following:                The number of the results corresponding to a search criterion is often high, and consequently overwhelms the user.        They do not provide easy means for distinguishing and noticing the results by their related content or subject.        The presentation of results is text-oriented, while presenting such an enormous amount of information overwhelms the user.        Although Google orders the search results by their importance (the number of links pointing to a Web site) this is not a precise criterion for the site's relevancy to the search goal, because the preliminary Web sites being ranked by Google was pulled out by text-oriented search criteria.        The human-compiled tree of categories is subjective and not objective.        Low cover rate at human-compiled directories (such as Yahoo and Looksmart).        
All the methods described above have not yet provided satisfactory solutions to the problem of the searching of Internet Web sites.
It is therefore an object of the present invention to provide a method and system for carrying out a search of Web sites, which overcomes the drawbacks of the prior art.
It is another object of the present invention to provide a method and system for carrying out a search of Web sites, which provides presentation of the Web sites, such that the visualization reveals certain attributes of the presented Web sites.
It is a further object of the present invention to provide a method and system for carrying out a search of Web sites, which classifies the Web sites according to their attributes.
Other objects and advantages of the invention will become apparent as the description proceeds.